President Donald Trump has returned to the White House from three days in hospital after contracting Covid-19.
Mr Trump has made it clear he is eager to put his three-night stay at Walter Reed Medical Centre behind him and played down the pandemic that has killed more than 209,000 Americans. “Feeling really good!” he tweeted. “Don’t be afraid of Covid.”
But, still, little is really known about the extent of the president’s illness or his care.
His doctors and aides are withholding key information on just how sick the president was, what risks lie ahead for Mr Trump as the illness progresses and under treatment by a novel combination of powerful medications, and whether the White House’s aides, security guards, cooks, cleaners and servers from infection by the still-contagious president.
Here’s everything we know:
Is the president better?
No. Mr Trump undergoes regular testing and the first positive result was some time after he returned from a Bedminster campaign event on Thursday evening and before being taken to the Walter Reed Medical Centre on Friday evening.
While he has been given a cocktail of drugs and treatments – the details of which remain vague – there is no confirmation that he is now testing negative.
White House doctor, Sean Conley, refused to say when asked if the president had a negative result and both physicians and medical bodies around the world advise that it can take 14 days or more to overcome Covid-19 and test negative and the US Centre for Disease Control and Prevention says those with mild to moderate symptoms – and it’s not clear if the president’s case falls within that range – should isolate for at least 10 days.
Dr Conley said that while the president was fit enough to go home, he “may not be entirely out of the woods” and that further care would be provided at the White House over coming days.
The doctor said the president could resume his normal schedule once “there is no evidence of live virus still present.”
What has the president said?
Mr Trump, a prolific tweeter, was initially quiet before sending out a raft of election slogans at the weekend. He appeared on several videos, appearing – uncommonly – without make-up from hospital saying he was OK. “Feeling really good!” he tweeted. “Don’t be afraid of Covid.”
On returning to the White House, he said: “I knew there’s a danger to it. But I had to do it. I stood out front. I led. Nobody that’s a leader would not do what I did. I know there’s a risk. I know there’s a danger. But that’s OK and now I’m better. Maybe I’m immune, I don’t know,” he said. There is no public evidence the president is immune to Covid-19.
What is the White House doing to contain Mr Trump’s infection?
The White House is facing criticism for not implementing proper social distancing measures, for a lack of mask-wearing in the West Wing and not communicating with those inside and outside about what is happening. It is unclear exactly how many presidential officials, White House staff or secret service members have now tested positive.
Within hours of Mr Trump's arrival at the White House on Sunday, officials announced measures including restricting access to the president and offering protective gear to those who meet him.
But Mr Trump appeared to flout the rules as he crossed the south lawn and entered the building, pausing on a balcony to remove his mask and give a thumbs up to reporters and supporters. He then went inside where he was greeted by a group of officials – still not wearing a mask – and recorded videos and posed for photos with official photographers.
But the White House is creating additional room for Trump to work in the residence, where he is staying with First Lady Malania Trump (who also tested positive last week) and avoid heading into the Oval Office, by converting the Map Room and Diplomatic Reception Room into office space, according to a person familiar with the matter.
Stephanie Grisham, the spokeswoman for first lady Melania Trump, said “all precautions are being taken” to safeguard those serving the ailing Trumps in the White House’s residential quarters, in consultation with the White House’s medical unit.
Who else has Covid-19
The exact number is unclear but at least a dozen staffers have tested positive.
White House counsellor Hope Hicks, one of Mr Trump's closest advisers, became ill with the coronavirus on Wednesday while accompanying Mr Trump to a fund-raiser in Minnesota, officials say.
It is not clear if her case is related to the President's. Mike Lee, a US senator who was at the White House last weekend, announced on Friday that he had tested positive.
The White House Medical Unit is believed say they are trying to trace the president’s contacts.
Several other key aides, including Press Secretary Kayleigh McEnany, have now also tested positive.
Members of the White House press pool are also being tested and three so far have had a positive result along with a White House staffer who sits in the "lower press" area of the West Wing.
Campaign adviser Chris Christie has also tested positive after being in contact with Mr Trump as has former White House adviser Kellyanne Conway and University of Notre Dame president John Jenkins.
The Secret Service has refused to disclose if any officers protecting the president have contracted Covid-19. But they insist that with the looming election thousands of officers are working and on standby and any agent who is experiencing symptoms can be quickly substituted.
READ MORE: Inside the White House ‘ghost town’
Who infected Trump?
US President Donald Trump reacts as he stands next to former White House Communications Director Hope Hicks outside of the Oval Office. Reuters
We do not know, although there is no shortage of possible suspects. Mr Trump, who typically shuns masks, was around hundreds if not thousands of people this week, travelling to a campaign rally, his golf club, the presidential debate, fund-raisers and meetings with people involved in his nomination of Amy Coney Barrett to the Supreme Court.
What symptoms does he have?
We don’t know how sick Trump got. We don’t know how sick Trump is now.
Dr Conley in daily news briefings at Walter Reed has detailed vital signs like temperature and blood pressure when they are normal, but repeatedly refused to give information that would indicate how serious the president’s respiratory troubles may have been, in particular.
Dr Conley also has failed to explain why Trump is receiving treatment typically reserved for difficult Covid-19 cases.
Mr Trump’s doctors said on Monday the president had refused to waive patient-doctor confidentiality to allow them to discuss the results of his lung scans. Covid-19 can cause significant damage to lungs. Scans reveal signs of pneumonia and other problems.
With treatment still evolving in the pandemic, Mr Trump’s doctors concede they themselves don’t know everything about the interplay of the medications he is taking. “We’re in a bit of uncharted territory,” Dr Conley said.
Disclosures at the weekend that the president’s blood oxygen levels had dropped below normal levels at least twice, and that he was receiving steroid treatment typically used in more serious cases, suggested the president was enduring more than a mild case of COVID-19.
Doctors say that Mr Trump will continue to receive his treatments from the White House.
Dr Conley said on Monday that Mr Trump “may not entirely be out of the woods yet” but he and the team “agree that all our evaluations and, most importantly, his clinical status support the president’s safe return home, where he’ll be surrounded by world-class medical care.”
White House Chief of Staff Mark Mr Meadows said on Saturday that Mr Trump's health, including a drop in his blood oxygen level, had left the president's doctors "very concerned" but that his condition had improved and there was never a risk he would have to hand over power to Vice President Mike Pence.
"He's made unbelievable improvements from yesterday morning when I know a number of us, the doctor and I, were very concerned," Mr Meadows said at the weekend.
"Yesterday morning, we were really concerned ... he had a fever and his blood oxygen level had dropped rapidly."
Several US media outlets said Mr Trump was on oxygen at the White House on Friday before being admitted to Walter Reed.
Mr Meadows' comments to Fox News capped a Saturday of back-and-forth in which conflicting reports about the president's health created an opaque understanding of his the leader's actual fitness.
At first, aides gave rosy assessments, with Mr Trump's chief of staff saying the president, 74, had only mild symptoms, was in "good spirits" and feeling "very energetic".
The president's son, Donald Trump Jr, told Fox News his father was "obviously taking it very seriously" and called him a fighter.
Another doctor treating Mr Trump, Sean Dooley, said at the weekend that the president's cardiac, kidney and liver functions were normal.
What care has he received?
On Friday began a five-day course of remdesivir, a Gilead Sciences drug currently used for moderately and severely ill patients. He received a single dose Friday of an experimental drug from Regeneron Pharmaceuticals Inc. that supplies antibodies to help the immune system fight the virus.
Mr Trump’s also received treatment with the steroid dexamethasone. It has only been proven to help in more serious cases. Among concerns with its use – steroids can tamp down the body’s own ability to fight off infection.
"He's being evaluated by a team of experts, and together we'll be making recommendations to the President and first lady in regards to next best steps," Dr Conley said.
Dr Coley said Mr Trump was also taking vitamin D, famotidine, which is typically used to treat heartburn and acid reflux, a sleep aid called melatonin and an aspirin.
Mr Trump apparently is not receiving hydroxychloroquine, a drug he widely promoted that has been shown in many studies to be ineffective for preventing or treating Covid-19.
Clinical trials have since shown the drug offers no substantial benefit.
When did Trump know he had been exposed?
It is still unclear if the president know of his infection and continued his campaign events and other activities.
White House officials say they learnt of Ms Hicks' positive test results for the coronavirus on Thursday after Mr Trump boarded the Marine One helicopter for a private fund-raiser in New Jersey.
But Mr Trump went ahead with the trip and the fund-raiser. He told Fox News that evening he was being tested.
Just before 1am on Friday morning, he tweeted that he and first lady Melania Trump had tested positive. Officials have insisted Mr Trump learnt of his infection after returning from the event in Bedminster.
What about the election?
Mr Trump's public-facing role in the campaign is effectively on hiatus for some time, even with election day in polling stations opening in only 31 days.
Guidelines from the Centres for Disease Control and Prevention say that anyone with a positive test must isolate for at least 10 days from the day they get the result.
That means a string of cancelled campaign rallies for Mr Trump. What it means for the next two presidential debates, scheduled for October 16 and 23, is still unclear.
Democratic presidential contender Joe Biden said on Monday he is willing to participate in next week's scheduled debate with President Donald Trump if health experts say it would be safe.
Vice President Mike Pence and challenger Kamala Harris will be separated by a Plexiglas barrier during their debate on Wednesday in an effort to lower the risk of coronavirus transmission, the commission overseeing the event said.
Both Ms Harris, a Democratic US senator, and Mr Pence, a Republican, have tested negative in recent days, with the vice president working from home at the weekend instead of at the White House.
The Commission on Presidential Debates also said the two candidates would be seated more than 3.7m apart. There will be a limited number of guests at the debate, all of whom will undergo testing, and anyone who does not wear a mask will be "escorted out," the commission said. Several of Mr Trump’s guests – including members of his family – removed their masks at the first debate last week.
While the Trump campaign is pivoting online, the vote will still go ahead. Indeed, early and postal voting has already begun nationwide.
If Mr Trump feels he is unable to run, he can withdraw and the Republican Party would choose someone else to step in.
What does it mean for the polls?
Before the announcement, Mr Trump was lagging behind his rival both nationally and in key states.
His debate performance last week did little to shift the numbers in his favour, but it is – according to pollsters – far too early to tell what the effect of Mr Trump becoming ill will have.
Nate Silver, of the prominent FiveThirtyEight polling analysis website, said he simply does not know how the polls will be affected.
“There’s an election happening literally now – millions of people have already voted. So, Americans are wrestling with this stuff. We just don’t have a lot of good answers,” he said.
“At a very basic, square-one level, Covid-19 is a huge liability for the President, and so placing more focus on Covid-19 probably isn’t great for him. But I don’t know how useful that is as a prior.”
But, new figures taken before Mr Trump said he was infected on Friday, showed that most Americans blame the government instead of foreign nations for the coronavirus crisis.
Although many see plenty of blame to go around and there’s a wide bipartisan divide over who is responsible, 56 per cent of Americans say the US government has substantial responsibility for the situation. That compares with 47 per cent who place that much blame on the governments of other countries and only 39 per cent who say the same about the World Health Organisation.
How have world leaders reacted?
Messages of support have flooded in from around the world with the likes of Russian President Vladimir Putin, UK Prime Minister Boris Johnson and an unlikely message from North Korean leader Kim Jong-un wishing Mr Trump well.
Mr Trump is the first world leader to receive a message wishing him a speedy recovery from Mr Kim.